Portion of a display screen showing a transitional icon



FIG. 1 is a front view of a first image of a portion of a display screen showing a transitional icon showing the new design; and,

FIG. 2 is a front view of a second image thereof.

The appearance of the design transitions between the images shown in FIG. 1–2. The process or period in which the design transitions among the Figures forms no part of the claimed design. The broken line drawing of a portion of a display screen is for illustrative purposes only and forms no part of the claimed design. 

The ornamental design for a portion of a display screen showing a transitional icon, as shown and described. 